Investigating the influence of taurochenodeoxycholic acid (TCDCA) on pancreatic cancer cell behavior: An RNA sequencing approach.

Pancreatic cancer (PC) poses a substantial global health challenge, ranking as the fourth leading cause of cancer-related deaths due to its high mortality rate. Late-stage diagnoses are common due to the absence of specific symptoms. Pancreatic ductal adenocarcinoma (PDAC) accounts for the majority of PC cases. Recent research has suggested a potential link between elevated serum levels of bile acids (BAs) and tumorigenesis of PDAC. This study aims to understand how taurochenodeoxycholic acid (TCDCA), a secondary BA, influences PDAC using RNA sequencing techniques on the Capan-1 cell line. We identified 2,950 differentially expressed genes (DEGs) following TCDCA treatment, with 1,597 upregulated and 1,353 downregulated genes. These DEGs were associated with critical PDAC pathways, including coagulation, angiogenesis, cell migration, and signaling regulation. Furthermore, we reviewed relevant literature highlighting genes like DKK-1, KRT80, UPLA, and SerpinB2, known for their roles in PDAC tumorigenesis and metastasis. Our study sheds light on the complex relationship between BAs and PDAC, offering insights into potential diagnostic markers and therapeutic targets. Further research is needed to unravel these findings' precise mechanisms and clinical implications, potentially improving PDAC diagnosis and treatment.

Down-regulation of USP22 reduces cell stemness and enhances the sensitivity of pancreatic cancer cells to cisplatin by inactivating the Wnt/ß-catenin pathway.

OBJECTIVE: Pancreatic cancer (PC) has the worst prognosis of all common cancers worldwide. This study was intended to investigate the role of ubiquitin specific peptidase 22 (USP22) in cisplatin sensitivity of PC cells and its regulatory mechanism. METHODS: The expression of USP22 and the toxicity of cisplatin to PC cells were detected. The two cell lines AsPC-1 and CAPAN-1 with the most differential drug resistance were selected. By down-expressing USP22 in CAPAN-1 cells and over-expressing USP22 in AsPC-1 cells, the survival rate of PC cells treated with cisplatin was detected. The mRNA expressions of stem cell markers, cell stemness, migration ability and apoptosis of PC cells were detected. The expression of Wnt/ß-catenin pathway related proteins was detected. The role of the Wnt/ß-catenin pathway in PC cell stemness and cisplatin sensitivity was explored after adding the inhibitor HLY78 and activator DKK1. RESULTS: USP22 was highly-expressed in PC cells, and the sensitivity of PC cells to cisplatin was negatively-correlated with USP22 expression. Downregulation of USP22 raised the sensitivity of PC cells to cisplatin, reduced the levels of stem cell markers, reduced the tumor sphere formation and migration, and promoted apoptosis. Silencing USP22 inhibited the Wnt/ß-catenin pathway. Inhibition of USP22 reduced the cell stemness and augmented the sensitivity of PC cells to cisplatin by inhibiting the Wnt/ß-catenin pathway. CONCLUSION: Silencing USP22 can inhibit the Wnt/ß-catenin pathway to reduce cell stemness and enhance the sensitivity of PC cells to cisplatin.

New Quinoline Based Sulfonamide Derivatives: Cytotoxic and Apoptotic Activity Evaluation Against Pancreatic Cancer Cells.

BACKGROUND: Quinoline is a privileged scaffold especially known with antimalarial and antibacterial drugs before, presently followed anticancer efficiency with a new group of protein kinase inhibitors. OBJECTIVE: In this work, combining quinoline ring, hydrazone and sulphonamide groups, we have synthesized N'-arylidene-2-[4-(quinolin-8-ylsulfonyl)piperazin-1-yl]acetohydrazide derivatives (3a-o) and evaluated their in vitro anticancer activity against cancerous cell lines PANC-1, CAPAN-1, and healthy cell line hTERT-HPNE. METHOD: Fifteen compounds were synthesized a simple, well-known three-step synthetic procedure starting from 8-quinolinesulfonylchloride. Cytotoxicity studies were performed according to the conventional MTT method. As a second stage, flow cytometric analysis was done to the nine most cytotoxic compounds for determining the mechanism of action which could be apoptosis and/or necrosis. RESULTS/CONCLUSION: According to anticancer activity evaluation, compound 3b bearing 4-methyl phenyl moiety exhibited significant cytotoxicity which has an IC50 value nearly four-fold lower than cisplatin displayed, whereas compound 3f bearing 4-trifluoromethyl phenyl moiety showed two-fold potency of the standard drug against PANC-1 cell line. Compounds 3h, 3k and 3n against CAPAN-1 also showed significant cytotoxicity, selectively. The most active compounds 3b, 3c, 3d, 3f, 3g, 3h, 3k and 3n against PANC-1 and compounds 3f, 3g, 3h, 3k and 3n against CAPAN-1 were selected to be studied in flow cytometry. Compound 3b induced apoptosis of PANC-1 cells with a percentage of 16.0%, whereas compound 3h induced apoptosis of CAPAN-1 cells with a value of 20.6%.

Development and In Vitro Characterization of a Gemcitabine-loaded MUC4-targeted Immunoliposome Against Pancreatic Ductal Adenocarcinoma.

BACKGROUND/AIM: Pancreatic Ductal adeno-carcinoma (PDAC) is a devastating disease. Gemcitabine is the standard chemotherapeutic agent against PDAC but has only limited effectiveness. The aim of the study was to develop and study the targeting affinity and in vitro antiproliferative effect of a MUC4-targeted gemcitabine-loaded immuno-liposome for treatment of PDAC. MATERIALS AND METHODS: Gemcitabine-loaded immunoliposomes were developed by grafting anti-MUC4 antibodies to the liposomal surface. Targeting affinity was compared in vitro between immunoliposomes and non-targeted liposomes and anti-proliferative effect was compared in vitro between free drug, non-targeted liposomal gemcitabine and MUC4-targeted immunoliposomal gemcitabine on a MUC4-positive pancreatic cancer cell line, Capan-1. RESULTS: Development of a MUC4-targeted immunoliposome was confirmed and characterized by immunoblots and size characterization. The MUC4-targeted immunoliposome showed a significantly higher targeting affinity compared to the non-targeted liposomes and also showed an improved antiproliferative effect compared to free and non-targeted liposomal drug. CONCLUSION: Successful development and characterization of a MUC4-targeted immunoliposome shows promising results for a targeted treatment and improved retention of gemcitabine for treatment of PDAC.

In vitro cytotoxicity evaluation of HDAC inhibitor Apicidin in pancreatic carcinoma cells subsequent time and dose dependent treatment.

Apicidin is a potent histone deacetylase inhibitor (HDACI) that selectively binds to histone deacetylases (HDACs) class I and interferes with the deacetylation process, which results in modification of acetylation level of cellular proteins. The aim of the study was to investigate the potential time and dose dependent cytotoxicity of the test compound, Apicidin, in pancreatic cancer cells Capan-1 and Panc-1 as well as estimate maximal tolerable dose (MTD) of the test agent and determine EC50 using four complementary colorimetric cytotoxicity or viability assays. The cells were treated with increasing concentrations of Apicidin (0-5000nM) for 2, 4 and 6h (short term exposure) or 24, 48 and 72h (long term exposure) before conducting cytotoxic analyses with lactate dehydrogenase assay or viability analyses with sulforhodamine B (SRB), methyl tetrazolium (MTT) and crystal violet (CV) assays. In order to investigate whether Apicidin irreversibly affects the cells already during the short term exposure, the medium containing Apicidin was removed and replaced with fresh culturing medium after 6h of treatment. The cells were then incubated for additional 24, 48 or 72h before carrying out the analysis. The results obtained from cytotoxicity and viability assays indicated, that Apicidin was well tolerated by both cell lines at concentrations below 100nM at any given time point and at all applied concentrations during the short term (6h or less) treatment. Continuous prolonged term exposures (48h or greater) of the cells to Apicidin with concentration exceeding 100nM resulted in significantly increasing cytotoxicity and sustained significant loss of cell viability. Moreover, long term exposure of pancreatic cancer cells Capan-1 and Panc-1 to Apicidin concentrations exceeding 100nM showed an initial anti-proliferative effect before cytotoxicity onset. In summary, MTD was exposure time dependent and estimated to 100nM for long term treatment and to at least 5000nM for treatment not greater than 6h. EC50 concentration of Apicidin was established after long term treatment, however with some variation when comparing the different assays and cell lines. Results from this study may encourage reinvestigating the capacity of potent HDACI Apicidin as an attractive agent for interfering with the deacetylation process catalyzed by HDACs for potential pancreatic cancer intervention.

Analysis of MUC4 expression in human pancreatic cancer xenografts in immunodeficient mice.

BACKGROUND/AIM: Mucin 4 (MUC4) is a cell surface glycoprotein that is overexpressed in most pancreatic tumors. The aim of the present study was to characterize MUC4 expression in experimental pancreatic cancer in order to clarify the correlation between MUC4 and pancreatic cancer histology in vivo. MATERIALS AND METHODS: Pancreatic xenograft tumors were generated in immunodeficient mice (n=15) by subcutaneous injection of MUC4(+) human pancreatic cancer cell lines Capan-1, HPAF-II or CD18/HPAF. MUC4 immunoreactivity was compared between the cancer models. Alpha-smooth muscle actin (α-SMA) was used to identify cancer-associated fibroblasts and the amount of collagen fibers was quantified with sirius red. RESULTS: Tumor incidence was 100%. Tumor size showed no difference across groups (p=0.796). The median MUC4 count was highest in Capan-1 tumors (p=0.002). α-SMA and collagen extent were also highest in Capan-1 tumors (p=0.018). CONCLUSION: The Capan-1 xenograft model could serve as a valuable resource to test new therapeutic strategies targeting MUC4 in pancreatic cancer.

Apicidin sensitizes pancreatic cancer cells to gemcitabine by epigenetically regulating MUC4 expression.

BACKGROUND/AIM: Mucin 4 (MUC4) has been linked to resistance to gemcitabine in pancreatic cancer cells. The aim of the present study was to assess whether epigenetic control of MUC4 expression can sensitize pancreatic cancer cells to gemcitabine treatment. MATERIALS AND METHODS: A 76-member combined epigenetics and phosphatase small-molecule inhibitor library was screened for anti-proliferative activity against the MUC4(+) gemcitabine-resistant pancreatic cancer cell line Capan-1, followed by high-content screening of protein expression. RESULTS: Apicidin, a histone deacetylase inhibitor, showed the greatest anti-proliferative activity with a lethal dose 50 (LD50) value of 5.17 µM. Apicidin significantly reduced the expression of MUC4 and its transcription factor hepatocyte nuclear factor 4α. Combined treatment with a sub-therapeutic concentration of apicidin and gemcitabine synergistically inhibited growth of Capan-1 cells. CONCLUSION: Apicidin appears to be a novel anti-proliferative agent against pancreatic cancer cells that may reverse chemoresistance by epigenetically regulating MUC4 expression.

Evaluation of 99mTc-HYNIC-βAla-Bombesin(7-14) as an agent for pancreas tumor detection in mice

Pancreatic adenocarcinoma is important in oncology because of its high mortality rate. Deaths may be avoided if an early diagnosis could be achieved. Several types of tumors overexpress gastrin-releasing peptide receptors (GRPr), including pancreatic cancer cells. Thus, a radiolabeled peptide derivative of gastrin-releasing peptide (GRP) may be useful as a specific imaging probe. The purpose of the present study was to evaluate the feasibility of using99mTc-HYNIC-βAla-Bombesin(7-14)as an imaging probe for Capan-1 pancreatic adenocarcinoma. Xenographic pancreatic tumor was developed in nude mice and characterized by histopathological analysis. Biodistribution studies and scintigraphic images were carried out in tumor-bearing nude mice. The two methods showed higher uptake by pancreatic tumor when compared to muscle (used as control), and the tumor-to-muscle ratio indicated that99mTc-HYNIC-βAla-Bombesin(7-14)uptake was four-fold higher in tumor cells than in other tissues. Scintigraphic images also showed a clear signal at the tumor site. The present data indicate that99mTc-HYNIC-βAla-Bombesin(7-14)may be useful for the detection of pancreatic adenocarcinoma.